The invention relates to an elastic bearing structure, particularly an elastic wheel support arm bearing for motor vehicles, with an inner bearing sleeve and an outer sleeve connected to the inner sleeve by an intermediate resilient structure with an axial cylindrical support area which is fixed to the center of a support member of a wheel support arm and which includes projecting end sections.
Elastic bearings of this type are used in practice as support structure for wheel support arms, for example for the mounting of the rear wheel suspension of, among others, the passenger cars type 190/190E of the series 201 of Daimler-Benz AG, which went into mass production in December 1982 and has been on the market for many years (see Mercedes-Benz Service, "Einfuhrungsschrift fur den Kundendienst" PKW-Typen 201 (190/190E) page 158, FIGS. 40/35). They are pressed with their outer sleeve into an eye of the respective wheel support arm wherein the press fitting (metal on metal) must insure firm engagement. As far as the bearing is covered by the eye receiving it, a certain corrosion protection is provided. The end areas of the outer sleeve projecting beyond the eye are subjected to ambient attacks. They should also be protected from ambient influences.
This is possible for example by an appropriate selection of the material of which the outer sleeve is made, for example, by making the outer sleeve of aluminum. This, however, has the disadvantage that the adjacent components such as the steel support arms do not consist of aluminum and are subjected to tension corrosion. It is also possible to galvanically coat the outer sleeves. This however requires careful assembly so that the protective coating is not damaged during assembly or at other occasions if the additional expenses for durable protection are to be justifiable.
DE-AS 10 66 056 discloses an elastic bearing in the form of a rubber sleeve spring which, in the embodiment as shown in FIG. 6, includes a sleeve-like insert arranged close to the inner and outer circumferences and which is vulcanized into the rubber body such that the rubber is compressed during installation whereby the rubber sleeve spring is fixed in the eye of the opposite part.
In the axial cylindrical support area, the sleeve-like inserts are expanded so as to be annularly bulged whereby the annular bulge penetrates the outer rubber spring layer and, in this way, comes into direct contact with the eye portion in which it is received. In this way, in addition to the fixing of the rubber sleeve spring by way of their radially inner or, respectively, radially outer rubber layer in the axial cylindrical support area of the rubber spring, the rubber spring sleeve is centered and, with the line-like support, an axial movement of the bearing is prevented even with high speed drives. The rubber sleeve spring is arranged in the known designs so as to extend over the full length of the respective bearing support structure so that the question of corrosion is not acute nor are there any corrosion tendencies with such designs.
It is the principal object of this invention to provide a support structure in which corrosion is prevented by simple and inexpensive means.